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View Full Version : hypevoxels aren't behaving !



sampei
12-16-2009, 11:00 AM
I'm rendering a scene where some particles fall towards the ground from mid-air.
The emitter is placed above the couch in a room and the characters are sat on in it. The problem is that when it renders the frame, the upper half of the screen is fine with all the voxels being rendered correctly while the bottom half of the screen wipes them all completely out leaving it as they were not there in the first place.
The way it is wiped out is very clean as if it was stoping rendering from the centre pixel horizontal row.
I noticed that turning off ray traced shadow they behave properly so I assumed its some shading problem. I tried tweaking the shading tab in the hypervoxel window but could not find what is causing this.
Any ideas ??? thanks in advance for the help

joelaff
12-17-2009, 04:50 PM
Have any transparent objects? Does it have to do with them? Are you rendering in a single segment (big enough segment buffer)? Does it happen you render at 50% of full resolution?

sampei
12-19-2009, 06:14 AM
hi joelaff sorry for the late reply and thanks for yours.
I have no transparent objects, it happens when I render at full res and could you explain the thing about the segment buffer ?
Anyway the wierd thing is this: I tried rendering the same exact scene on a different machine (my own) and gave me no problems.
Later in the animation I had more hypervoxels animated to fly upwards.
It did the same thing (on my machine) as in a "rectangle" in middle of the hypervoxels area was not lit and appeared to be almost invisible and I managed to solve this changing the lighting for the HV to rayleigh (I had it on beer) and it solve this problem. I'd really want to know why it was doing this

mike_stening
12-21-2009, 04:38 AM
some pics or screen shots might help with this, as i kinda follow what you are saying but i could be well off the mark.
it almost sounds like what joelaff was saying that it was rendeing the frame in 2 segments, top then bottom, which could explain the half screen only voxels, top half as that is rendered first.
segment buffer (segment memory limit) is the amount of ram you give to the renderer to render the frame, too small and it splits the frame into horizontal strips, you really want this set to 1 segment, the default setting is 32mb which is usually way too low for most uses.

sampei
12-21-2009, 05:10 AM
hey Mike I'll try and post some renders if I can find them, as I said changing machine solved this (well for the first batch of voxels) which could mean that the segment memory limit is probably the culprit. I'll run a couple of tests and try and grab some renders so you see what I mean, but at least the animation is finally finished and ready to be handed in :D

sampei
01-07-2010, 10:19 AM
sorry for the late reply, been kinda busy ! anyway I finally got my hands on one of the faulty frames so here it is...in this one the voxels actually disappear as you can see. While on the other emitter they were shaded differently, almost transparent...
http://i375.photobucket.com/albums/oo198/ONM-Sampei/SPS2A_1965copy.jpg
Ill see if I have time to test the segment memory theory and solve this mistery :hey:

toby
01-07-2010, 05:25 PM
It might also work if you turn off multi-threading, but slowly of course -